During gas turbine engine assembly, the tie shaft is stretched as part of the preload process for the rotors stack. The amount of stretching force applied to the tie shaft to achieve the required preloading of rotors stack typically must be augmented to compensate for friction between the tie shaft and a rear hub. The amount of friction may be inconsistent and difficult pre-determine. To avoid applying “extra” stretch force to the tie shaft, it may be beneficial to reduce the friction between the tie shaft and the rear hub during gas turbine engine assembly.